Reconstruction and identification of $H\to W{W}^{*}$ with high transverse momentum in the full hadronic final state

This paper presents a study of the reconstruction and identification of $H\to W{W}^{*}$ with high transverse momentum, where both $W^{(*)}$ bosons decay hadronically. We show that the boosted $H\to W{W}^{*}$ can be effectively reconstructed as a single jet and identified using jet substructures in the center-of-mass frame of the jet. Such a reconstruction and identification approach can discriminate the boosted $H\to W{W}^{*}$ in the full hadronic final state from QCD jets. This result will significantly improve experimental sensitivities of searches for potential new physics phenomena beyond the standard model in final states containing highly boosted Higgs bosons.

Figure 1

The reconstruction efficiency of a hadronically decaying $H\to W{W}^{*}$ using a single jet as a function of the Higgs boson $p_T$. The Higgs bosons are required to have $|\eta |<2.0$.

Figure 2

The track-assisted jet mass distribution of signal $H\to W{W}^{*}$ jets (solid line) and QCD jets (dashed line) in different $p_T$ ranges.

Figure 3

The distributions of the jet substructure variables calculated using energy clusters (top row) of a jet or charged tracks (bottom row) associated with the jet for $H\to W{W}^{*}$ signal jets (solid line) and QCD jet background (dashed line) in different jet $p_T$ ranges. Highly directional distributions of energy clusters or charged tracks have $T\approx 1$, $T_{\min }\approx 0$, $S\approx 0$, and a large value of $R_2$, while $T\approx 0.5$, $T_{\min }\approx 1$, $S\approx 1$, and a small value of $R_2$ correspond to an isotropic distribution. All the distributions are normalized to unity.

Figure 4

The background rejection of QCD jets vs the signal efficiency of $H\to W{W}^{*}$ jets in different jet $p_T$ ranges, where the background rejection is defined as $1/{\epsilon }_{\mathrm{bg}}$ and ${\epsilon }_{\mathrm{bg}}$ is the misidentification efficiency of the background QCD jets for a given signal identification efficiency.

Figure 5

The expected 95% C.L. UL on the product of the production cross section of a heavy resonance $X$ and its decaying branching faction into a Higgs boson pair, as a function of the assumed $X$ mass that is reconstructed in different Higgs boson decay final states.